President Donald Trump made good on his threats to attack Syria Friday night, launching what he called "precision strikes" against three chemical weapons sites in a military action certain to enrage Russia and raise new questions about his Middle East strategy.

Trump announced the strikes in a somber televised address less than a week after what U.S. officials call a poison gas attack on civilians conducted by Syrian leader Bashar Assad’s regime.

Story Continued Below

"These are not the actions of a man," Trump said, referring to Assad. "They are crimes of a monster."

"The purpose of our actions tonight is to establish a strong deterrent against the production, spread, and use of chemical weapons," Trump said.

Though more substantial than an April 2017 attack Trump ordered on a Syrian airbase—also as punishment for the gassing of civilians—Friday's action did not open a new phase of American involvement in Syria, where Trump’s larger strategic goals remain unclear.

Although Trump said Friday that he is “prepared to sustain this response,” he also stressed that he does not intend to stay long in war-torn Syria, where roughly 2,000 U.S. troops have been fighting the Islamic State.

“America does not seek an indefinite presence in Syria — under no circumstances,” he said.

Trump on Saturday morning heralded a "perfectly executed strike," praising the military and tweeting that it was "Mission Accomplished!"

At a Pentagon briefing late Friday night, Secretary of Defense James Mattis and Joint Chiefs of Staff Chairman Gen. Joseph Dunford said the strikes were limited to Syrian chemical weapons facilities and did not target Syrian troops or military assets.

While Syrian air defenses did fire at some U.S. aircraft or missiles, Mattis said there had been “no reports of losses” to U.S. forces. And despite previous threats from Moscow to shoot down U.S. cruise missiles, Dunford said he was not aware of any response by Russia's military, which has fought alongside its ally Assad for years in Syria's brutal civil war.

Dunford added that the U.S. had used a pre-existing “deconfliction” line of communication with Moscow, adding: “We did not do any coordination with the Russians on the strike, nor did we pre-notify them.”

Flanked by Dunford and the British and French defense attaches, whose militaries assisted the U.S. operation, Mattis called the attacks a “one-time shot.”

The attacks were on a smaller scale than some analysts had predicted, reasoning that Trump needed to send a tougher signal than he did a year ago given that his last strike had clearly not deterred Assad’s continued use of chemical weapons as a tool to put down an armed rebellion that has raged since early 2011.

Mattis said his confidence that the Syrian regime was responsible for the recent chemical attacks increased yesterday, after congressional testimony in which he suggested a degree of doubt. “We are very confident that chlorine was used. We are not ruling our sarin right now,” he said.

Trump's eight-minute statement included some of his sternest words to date for Russia, which he said had not done enough to contain its ally Assad and was, he said, "associated with the mass murder of innocent men, women, and children."

"Russia must decide if it will continue down this dark path or if it will join with civilized nations as a force for stability and peace,” Trump said, as his new national security adviser, John Bolton, looked on.

"Hopefully, someday we’ll get along with Russia... but maybe not," Trump added. He did not specifically name Russian President Vladimir Putin, whom he virtually never criticizes personally.

The strike is a response to a suspected chemical weapons attack in in the Syrian town of Douma, north of the capital of Damascus. The attack, which Trump called “evil and despicable,” killed dozens of people.

Dunford said that the strikes began at 9pm Eastern Time and involved both cruise missiles and manned aircraft. The U.S. struck three different targets in the attack, Dunford said: a scientific research center outside Damascus, a chemical weapons facility west of Homs and an equipment storage facility and command post.

Other Syrian checmical weapons facilities were not struck, Dunford said, due to concerns about harming civilians.

Asked if the strike will be part of prolonged military action in Syria, Mattis said “that will depend on Mr. Assad.”

British Prime Minister Theresa May said in a statement that the Syrian regime "has a history of using chemical weapons against its own people in the most cruel and abhorrent way. And a significant body of information including intelligence indicates the Syrian Regime is responsible for this latest attack."

"This persistent pattern of behavior must be stopped," May said, adding that "we cannot allow the erosion of the international norm that prevents the use of these weapons."

Trump also said Friday’s strike was intended to establish a “strong deterrent” against the future use of chemical weapons.

That is no sure thing, analysts warn: One concern among western officials is that Assad will lay low and avoid using chemical weapons for a while—before returning to them after international attention shifts. Some critics also question why the U.S. and its allies are moved to action by chemical weapons but not horrific conventional attacks on hospitals and civilian neighborhoods.

The Russian Ambassador to Washington, Anatoly Antonov, warned the U.S. and its allies that “such actions will not be left without consequences.” In a statement, he also appeared to implicitly chide Trump, saying that “insulting the President of Russia is unacceptable and inadmissible.”

The U.N. Security Council met Saturday at Putin's request, where U.S. ambassador Nikki Haley stressed the case for the strikes, saying the U.S. is "locked and loaded" in the event chemical weapons are deployed.

Earlier this week Trump, who has spent most of his presidency avoiding publicly criticizing Russia or Vladimir Putin, called out the Russian president by name on Twitter, saying he was among those “responsible for backing Animal Assad.”

Trump’s decision comes after another chaotic week in Washington that started with an FBI raid on the apartment and office of Michael Cohen, Trump’s personal lawyer, and ended with a barrage of news reports on former FBI Director James Comey’s tell-all book.

Trump, for his part, has been angry all week, fuming to aides about special counsel Robert Mueller’s investigation and Comey’s personal attacks on him in the book.

All the while, Trump and his national security team were fiercely debating a Syria response behind the scenes.

On Monday, Trump said his administration would decide in the next “24 to 48 hours” on a response. But an internal debate delayed action, with some in the administration, including Mattis, urging caution.

Mattis expressed no reservations in his Friday night remarks.

“Clearly the Assad regime did not get the message last year. This time our allies and we have struck harder,” the Marine general said, noting that tonight’s strikes had hit three targets instead of one, using twice as many weapons as last year’s operation.

Vice President Mike Pence, in Peru for the Summit of the Americas, spoke with congressional leaders from a secure line at his hotel to inform them of the strike, according to Pence spokesman Jarrod Agen.

Dunford said that the strikes began at 9pm Eastern Time and involved both cruise missiles and manned aircraft, as well as both French and British military resources.

The first target, Dunford said, was a facility near Damascus where chemical weapons were manufactured. The second and third targets were chemical weapons storage and command-and-control facilities near Homs.

Other Syrian checmical weapons facilities were not struck, Dunford said, due to concerns about harming civilians.

While May said the Western strikes were not about regime change, the decision to attack the Damascus area, Assad’s seat of power struck some analysts as an important signal to Assad. It suggested the U.S. wasn’t afraid of “hitting command and control infrastructure and sending a clear message to Assad and his leadership clique that they are not safe,” said Randa Slim an analyst at the Middle East Institute.

The president's decision to retaliate drew swift support from his own party.

“Chemical attacks against innocent children and civilians are horrific and totally unacceptable," U.S. Senator David Perdue (R-GA), a member of the Senate Armed Services Committee, said in a statement. "President Trump is engaged and led our allies in measured response to hold Assad accountable."

House Armed Services Committee Chairman Mac Thornberry (R-TX) called Assad's the use of poison gas "unacceptable" and saying the attack is “part of a trend of Russian supported chemical weapons attacks across the world.”

“Tough questions about the future of our policy in Syria remain, but those questions should not detract from the justness of tonight’s actions," Thornberry concluded.

The strike was also praised by some Obama administration officials who have advocated for a tougher American approach to Assad.

“No way am I happy that the Syrian people have to endure more, but seven years of impunity has to have consequences,” tweeted Wa’el Alzayat, a former State Department official who dealt with Syria issues.

But anti-war groups were quick to criticize the move as reckless and unlikely to make a difference in the long run. Peace Action declared Trump’s strike “impulsive, dangerous and a clear violation of domestic and international law," saying it “endangers U.S. forces in the region, and invites escalation from Russia, Iran and Syria.”

Sen. Tim Kaine (D-Va.), and a long-time opponent of military action without a express congressional authorization, called Friday night’s strike “illegal,” saying Trump required the approval of Congress.

"Presidents cannot initiate military action when there isn’t an imminent threat to American lives," Kaine added. "Today, it’s a strike on Syria — what’s going to stop him from bombing Iran or North Korea next?”